Highlighting coral reefs at risk

Weighing more than 300 kilogrammes, the giant Turbinaria bifrons was collected from Shark Bay Reef, off the coast of Western Australia, more than 120 years ago.

Principal Curator Miranda Lowe says the Turbinaria, one of the largest specimens in the Museum's marine invertebrates collection, provides a timely reminder of the importance of coral reefs as well as human impact on underwater ecosystems.

This coral (pictured below) would have provided sanctuary for thousands of sea creatures including oysters and plants amid its complex system of crevices, layers and branches.

'A great number of animals would have lived or been associated with the coral - for not just shelter but also food,' Miranda says.

'This one coral would have been home to multiple species of fish and filter-feeders like molluscs, sponges and serpulid tube worms. Sheltering everything from microscopic food to fish for turtles, it was a whole ecosystem in itself.'

The giant Turbinaria coral going into Hintze Hall has been in the Museum for 150 years

'Human impact on the reef can be great and sudden, and this specimen is a prime example of that,' Miranda says.

'It's a reminder that if we don't have coral reefs, we lose thousands of species of fish and eventually commercial economies and food supply as well - because without the reefs you don't have the diversity of fishes.'

Claiming an underwater giant

The piece of coral going on display is a Turbinaria, a genus of colonial stony corals native to the Red Sea, the Indian Ocean, Japan and the South Central Pacific Ocean, which grows in a cup shape on the reef.

It is one of four large pieces collected in the late nineteenth century by the British naturalist and marine biologist William Saville-Kent.

Devon-born William Saville-Kent was Commissioner for Fisheries in Western Australia between 1892-1895

In his journals, he describes in great detail the challenge of retrieving this one–metre-wide Turbinaria.

'They used crowbars to pry it off the reef, but it was so heavy that they couldn't get it up onto the deck of the ship,' Miranda explains.

'They had to tow it in to shore and deposited them has high up on the beach as the tide would permit, then waited for low tide to examine and move them. It took a dozen men to winch it on board steamers to bring it back to London.'

Cringing at the mention of crowbars, Miranda was quick to point out that in the age of exploration, the way scientists approached the reef was different to how they work today.

'At that time they were collecting everything that looked new or interesting, for curiosity as well as for science.'

A breakthrough on the reef

This Turbinaria also led to an important breakthrough in scientific understanding.

According to Miranda, having such a large specimen allowed scientists to properly identify coral for the first time, because the corallites - the tiny holes that give coral a pitted surface - were large enough to see partly with a naked eye and with microscopes of that time.

This close-up image shows the small corallites on the specimen. A corallite is the skeletal cup formed by an individual coral polyp.

Scientists have since used the details of corallites to identify coral.

In 1896 the Turbinaria had pride of place in the Museum's corals gallery, but it spent the majority of the last century in storage before Miranda rediscovered it in 1993.

'It's quite a robust specimen,' Miranda says. 'Aside from a gentle cleaning and a new base, very little conservation work has been needed in 150 years.'

From crowbars to conservation

Scientific approach to coral reefs has changed drastically over the last 120 years.

'Looking across some of the historical specimens, they tend to be much larger than recent samples as maybe they had the opportunity to grow so large without human interaction,' says Miranda.

However, 'for the purpose of coral identification, scientists in Victorian times preferred pristine-looking specimens, so they were bleached and scrubbed clean.'

Such harsh handling is no longer commonplace. 'Molecular scientists are always asking me for unbleached materials with organic matter still attached, so we have had to rethink the way we treat specimens.'

Many of the Museum's coral specimens were gathered in the 1970s. They are much smaller than those retrieved in Victorian times, and today they are even smaller. Many of the source reefs are classified Marine Protected Areas and 'no-take zones', where taking anything from the reef is prohibited.

Miranda believes the Museum has a new role to play in the study of climate change and its effect on the reef.

'Pristine historical collections can also feed into contemporary research and long-term comparative work on the living reef,' she says.

The coral being installed in Hintze Hall

Can our coral reefs recover?

Climate change, ocean acidification and human interference have caused a great deal of damage to the world's coral reefs. It is difficult to accurately determine whether the reefs can recover.

According to Miranda, the growth rate of coral is highly dependent on what species it is, the environment and the nutrients in the water.

'The short answer to a difficult question is that coral reefs can recover over time, but the way they grow back will be different. They don't have so many diverse species and they don't flourish as they once did.'

For example, 'after a coral bleaching event, certain kinds of branching coral can grow back prolifically while other types, which are slower to recover, can be overtaken by those better adapted to environmental change.'

Ongoing scientific research on corals is needed to help us understand and predict the impact of humans and climate change on our oceans, one of the biggest challenges facing our natural world today.

Visit the Museum

The giant Turbinaria is on display in the newly refurbished Hintze Hall.